This invention relates to the autoxidative cleavage of selected ketones having at least one hydrogen on carbon alpha to the carbonyl carbon, such as C.sub.4 -C.sub.10 cycloalkanones and aryl alkyl ketones, comprising contacting a liquid phase comprising said ketone with elemental oxygen gas in the presence of a pulverized alkali metal hydroxide at a temperature of no more than about 50.degree. C. for a time sufficient to produce an oxidized product.
Autoxidations of organic compounds such as hydrocarbons and ketones use molecular oxygen and are catalyzed by base. Base-catalyzed autoxidations usually employ strong bases such as alkali metal amides, hydrides or alkoxides and are known to effect cleavage of the carbon-carbon and carbon-hydrogen bonds alpha to the carbonyl carbon. For example, cyclohexanone, in the presence of base, is autoxidized into alpha-hydroperoxycyclohexanone and cyclohexane-1,2-dione (products of carbon-hydrogen bond cleavage) and condensation products of the ketone starting material and diketone product or is autoxidized into reaction mixtures containing adipic acid, lower diacids (products of carbon-carbon bond cleavage) and product(s) of carbon-hydrogen bond cleavage and mixtures of condensation products including condensation products of carbon-carbon cleavage products and of the ketone starting material.
Prior art base-catalyzed autoxidations are homogeneous, produce complicated product mixtures, consume at least stoichiometric quantities of strong base, operate under anhydrous as well as homogeneous conditions with aprotic solvents such as hexamethylphosphoramide and molecular oxygen gas and usually at temperatures below 0.degree. C. Accordingly prior art base-catalyzed autoxidations produce complicated product mixtures, poor selectivities and as such are economically unattractive for commercial scale operation.